As Unites States and European leaders prepared to impose sanctions against those responsible for the deaths in Tuesday's clashes between protesters and government forces in Ukraine, President Viktor Yanukovich said late Wednesday he agreed to a "truce" with opposition leaders.

Yanukovich held talks with the former Soviet Union nation's three main opposition leaders and they agreed to a truce and "the start to negotiations with the aim of ending bloodshed, and stabilizing the situation in the state in the interests of social peace," according to a statement on the presidential website.

"The storming of the Maidan (Independence Square in Kiev) which the authorities had planned today will not take place," one of the opposition leaders, Arseny Yatseniuk, said in a statement. "A truce has been declared. The main thing is to protect human life," added Yatseniuk, former economy minister.

The move comes as U.S. and European leaders condemned the death of at least 26 people in clashes between protesters and security forces on Tuesday.

"We hold the Ukrainian government primarily responsible for making sure that it is dealing with peaceful protesters in an appropriate way," U.S. President Barack Obama said Wednesday. "We're going to be watching closely, and we expect the Ukrainian government to show restraint, to not resort to violence in dealing with peaceful protesters."

The U.S. State Department said 20 senior members of the Ukrainian government would be barred from visiting the United States – without identifying the officials.

Pentagon spokesman Colonel Steve Warren asked the Ukrainian armed forces to stay out of the conflict, warning that "participation would have consequences in our defense relationship," according to Reuters.

"The European Union will respond to the deterioration on the ground, including via targeted measures," European Council President Herman Van Rompuy said in a statement.

However, EU officials said the Ukrainian president would be excluded from such measures so that channels of dialogue remain open.

Despite the announcement of a truce, explosions were heard late Wednesday, CNN reported. Protesters continued to pick up pavement and rocks and throw them at police, who responded in some cases by throwing Molotov cocktails.

"The government would like the world to believe that those on Maidan are just terrorists and extremists to justify the bloodshed... that those on Maidan are armed with firearms and rioting," a protester, MaiaKiev, was quoted as saying. "But it's not a riot ... It's a revolution of dignity."

At least 26 people, including some police officers, were killed and about 1,000 others were injured as police carrying stun grenades and water cannons stormed a protest encampment at the Independence Square Tuesday.

Police beat more than 25 journalists who were there to cover the violence. At least 100 police officers were also injured, including dozens from gunshot wounds.

Anti-government demonstrations began last November to demand the nation's closer European integration, after the administration suspended preparations for signing an Association Agreement and a Free Trade Agreement with the European Union, in favor of closer economic relations with Russia.